With the development of mobile communication and the continuous evolution of 3G technology, the transmission speed of wireless data card terminal becomes higher and higher, and the size of the terminal becomes smaller and smaller. Thus heating of the data card becomes a significant problem. In general, after the data card operates for a period of time, the heating phenomenon occurs very easily. Therefore, some wireless data cards are even hot, which tends to cause the element aging and element damage, and may scald the user or cause fire.
Aiming at the problem, there are following two main solutions at present: optimizing the external design of the data card and decreasing the transmission power of the wireless terminal. The solution of optimizing the external design of the data card is selecting material with good heat dissipation and optimizing the external structure of the data card. For example, punching or notching on the metal material to increase the heat dissipation area is one of the solutions. However, this way cannot solve the heating problem of the data card radically and increases the cost. The next solution of decreasing the transmission power of the wireless terminal deems that heating of the wireless terminal mainly results from power amplifier, and heating of the power amplifier relates to uplink transmission power. That means the temperature of device is controlled by decreasing the transmission power when the temperature reaches a certain threshold. The transmitter is immediately turned off when the temperature continues increasing to reach an emergency threshold. Also, the transmission power is gradually increased to a normal value when the temperature decreases to a certain threshold. The solution of decreasing the transmission power of the wireless terminal is disadvantaged in that decreasing the transmission power may cause failure of accessing the network for the weak signal, thereby affecting user experience.
To sum up, all of the traditional arts fail to effectively solve the heating problem of the data card.